This invention relates, generally, to pinball games and, more particularly, to an optical ball sensor for such games.
Pinball games typically consist of an inclined playfield supporting a plurality of play features, a rolling ball and player operated flippers for directing the ball at the play features. One such play feature is the, so called, roll-over switch. A roll-over switch typically consists of a wire or other activator extending through an aperture in the playfield. The switches are located such that the ball can roll over the activator thereby depressing it to close a switch and deliver a signal to the game microprocessor.
These switches are relatively complicated and time consuming to manufacture and install because they have numerous components that must be assembled and aligned. In addition to these problems, game manufacturers have found it desirable to continually modify and improve their play features to maintain player interest in their line of games. Thus, alternatives to existing play features are continually developed. One such alternative to the mechanical roll over switch is a magnetic roll over switch disclosed in U.S. Pat. No. 4,542,905 to Hooker that has a magnetic sensor mounted below the playfield that senses the presence of a ferromagnetic ball. Moreover, an optical target assembly is disclosed in U.S. Ser. No. 07/847,355 assigned to the present assignee.
An alternative ball sensor is desired including one which avoids the need for alignment and/or periodic adjustment as was the case with prior art rollover switches.